計唔到 唔該幫我計一計 thz!!
1. find the values of k.
{ x^2 - 4y^2 + 20 = 0
{ x + 3y + k = 0
2. solve the following equations.
3x - 開方2x+1 = 9 <-- (成個 2x+1 開方)
3. solve the following simultaneous equations using the algebraic method.
{ x^2 + y - x = 1
{ 2x + 3y = 1
answers :
1. k = +5 or -5
2. x = 4
3. ( -1/3 , 5/9 ) , ( 2 , -1 )
thank you !